Wetlands are areas that are saturated with water (freshwater or saltwater) and covered with aquatic plants. They are literally wet land, or a transition between dry land and a larger body of water. Wetlands are home to a huge amount of plant and animal life. They are also important ecosystems that store water, prevent flooding, purify water, and store carbon.
There are many types of wetlands, including: swamps, marshes, fens, and bogs.
Low lying land that gets flooded during high tides or wet season. Marshes can be found on the edges of lakes or streams. They typically remain waterlogged all year. Marshes are often dominated by grasses or reeds and are home to many bird species.
Marshes can be divided into three categories. Tidal salt marshes form a grassy barrier along bays, river mouths, or protected coastline. They rise with the ocean tides twice a day.
Tidal freshwater marshes are further inland, and while they still rise and fall with the tides, they are fed with freshwater streams.
Inland marshes are found at the edges of lakes or rivers. They may not have standing water most of the year and thus have little vegetation but many insects, frogs, and snakes. Or they can be covered in water all year, and have vegetation and animals like ducks, alligators, and turtles. The Everglades and the Okavango Delta are two big inland marshes.
Swamps are dominated by trees, and are found both inland and in coastal areas. Freshwater swamps are inland and are usually located by lakes or rivers. They have birds, fish, and amphibians living there. Alligators and panthers can also be found in some freshwater swamps.
Saltwater swamps are on coastlines and may have mangrove trees growing in them. Many fish spawn in the safety of the mangrove roots, and their small offspring will spend their time there until they are mature enough to swim out to sea. Birds and shellfish are also abundant in saltwater swamps.
Bogs and Fens
Bogs and fens are both characterized by peat- a layer of vegetation that is poorly decomposed.
Bogs are not connected to streams or lakes, but are able to store water from the surrounding land. They do not have many types of plants.
Fens, on the other hand, are connected to streams or lakes, and have a wider range of life.
Wetlands are an extremely important ecosystem (or biome).
They prevent flooding from rain or storm surges by soaking up the excess water like a sponge.
They also hold on to water for periods of drought, and help stop fires from spreading.
Wetlands are home to a wide variety of animals and plants.
Wetlands filter the water so it runs cleaner to the next water body. Sediment settles, and nutrients and toxins are absorbed by plants and microorganisms.
Wetlands also store carbon, which helps in the fight against climate change.
Animals that live in wetlands
Cranes pair off to breed and often stay with the same mate for life. They raise their young together and the chicks stay with their parents until the next breeding season. During the non-breeding season, cranes are social and congregate in large flocks. Cranes are also very vocal and mates have specialized duets that they sing, taking turns adding notes.
Beavers are sophisticated engineers, shaping their environment more than any other animal (except humans). They chew down trees and drag them to the water to create dams- blocking the flow of water to create ponds to live in. They align long poles against the banks and weigh them down with heavy rocks, then stuff grass in the cracks until it effectively traps water.
They also use these trees to build lodges to live in. They are either a series of tunnels and holes on the banks with sticks piled on the top or built on the water on a platform of sticks with a roof sealed with mud. Both types of lodges are accessed by an underwater entrance.
Beavers create wetlands when they build dams and alter stream paths. More plants can grow in the wetlands they create. The new wetland increases the number of salmon and trout, frogs, turtles, and waterfowl as well.
Salamanders are amphibians. Most species lay their eggs in the water, which is where the lavae also grow up. Adults live fully in the water, on land, or a combination, depending on the species. They are able to regrow limbs and other body parts if lost. However, to avoid being eaten in the first place, many salamander species are toxic, and display bright colors to warn predators.
Threats to Wetlands
The introduction of invasive plants (non-native species) can push native plants out of the habitat, which may also wipe out animal species that relied on those plants. The introduction of invasive animal species can also push out native animals.
Allowing livestock, like cows, to graze along wetlands removes plants and causes erosion which can clog up the waterways.
Wetlands are sometimes drained, converted into farmland, or water is diverted.
Companies build over wetlands to make roads or buildings.
The loss of wetlands causes more erosion and more sediment to enter water bodies. This can kill off the plants and even aquatic animals as the water clouds up and prevents light from getting through the water. When wetlands disappear, so do many of the plants and animals that relied on that habitat to eat or breed or live. Without wetlands to filter out nutrients and chemical runoff they would pollute the next water body, making the water uninhabitable for some plants and animals.
How you can help
Never release an animal into a habitat that it is not native (for example, taking your pet turtle and dumping it in the nearest lake). Also be careful not to plant non-native plants or seeds.